Base for a cylindrical tank



FIG. 1 is a perspective view of a base for a cylindrical tank showing my new design, on a reduced scale;

FIG. 2 is a top plan view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a side elevational view thereof; and,

FIG. 5 is a rear elevational view thereof. 

The ornamental design for an base for a cylindrical tank, substantially as shown. 